Uwited btjltes f



JOHN JACK, IOB NUNDA, NEW YORK, ASSIGNORTO ALFRED BELL.`

` wioKnrroR LOCK-GATES.

specification `of Letters Patent No. 7,379, dated May a1, 1850;

same, making part of this specification, in

whichi Figure l is a side elevation of a lock gate with my improvedwicket applied thereto, Fig. 2 is a view in perspective of the gatepartially opened, its seat also being seen, and Fig. 3 is a sectiontaken through the line A A of Fig. 2.

My invention and improvement consists in making and arranging a slidingwicket or sluice gate so that when shut, it shall rest upon its seat,so' as to make a tight joint, but when in the act of opening or closingshall be raised therefrom, and be carried on wheelsthereby diminishingthe friction and the power required to operate it, the power for raisingthe gate being applied through a lever or its equivalent so as to movethe gate very slowly, but with great force, until it is started from itsseat and its weight is thrown upon the friction wheels, and then, to actupon it with less force, but to move it faster, until it is fullyopened.

One leaf (A) of a pair of folding lock gates is shown in Fig. l with myimproved sliding wicket (B) applied thereto; this wicket is of an oblongrectangular shape, and is fitted with friction wheels (h h) on which itruns when in the act of opening or shutting. The lower edge of the gateis iitted with aflange (le) which inclines outward and is of such widththat the upward pressure of the water beneath it will be sufficient tocounterbalance the pressure on the upper edge of the gate, added to theweight of the gate and its appendages; the inclination of this flange issuch, that notwithstanding the effect of the een@ contracte, the issuingwater will act against it, and tend to raise the gate with the sameforce after it is partially opened, as when it is closed.

The seat of the gate, as represented, consists in this instance, of aframe of metal having tracks formed on its ends for the end wheels ofthe gate to run on, and two arms (rr) `projecting upward from its upperside on `which tracks are formed for the side wheels` to run on, theseseveral tracks are straight; throughoutthe greater part oftheir lengthbut each is sloped off on its lower end, thus forming an inclineddepressiony(g) down which the wheels run `to lower the: gate upon itsseat, and thus make a `tightjoint` when it shuts; the depth to which^thewheels drop when the gate closes measuresthe distance which the gateraises off its seat `when moving toward or from its shut position. It isplain that the gate must be moved against the pressure of the wholecolumn of water resting against it when it is run on its wheels up theinclined to the straight parts of the tracks, but after the wheels areonce on the straight part o-f the tracks, there is no other resistanceto be overcome than that of the friction caused by the pressure of thewater, and the slight friction of the moving parts. Hence it willappear, that a far greater amount of force is required to start the gatefrom its seat and run the wheels up the in clined planes, than isafterward required to run it up the tracks to the wide-open position.

By referring to Fig. l it will be seen that the hand lever (P) by whichthe power is applied to move the gate is so arranged,

that its fulcrum is in a line with the' connecting rod (p) and thejoints by which the rod is connected with the gate (B) and the lever (P)respectively, when the gate is shut, so that a small amount offorce'applied to the upper end of the lever (P) in the direction of thearrow (e) will produce a strong pull through the rod (p) on the gate,and while the upper end of the lever (P) sweeps through a veryconsiderable space the gate will be moved a very small distance, butsuflicient to raise it from its seat, and throw its weight upon thefriction wheels; as the motion of the upper end of the lever iscontinued, the effective length of its lower end will be rapidlyincreased, and will pull with less force upon the gate, and move itfaster, but the gate being no-w raised from its seat and the wheelsrunning upon the straight part of the track, requires less force to moveit, and thus the varying resistance opposed by the gate in raising, ismet by a correspondingly varying force produced through the changingposition of the lever by a given extremity. This sliding Wicket may bemade of the usual or any convenient form and of any suit-able materialand may be varied in any of its details at the option of theconstruct-or, provided it rests upon its seat When shut, and is raisedtherefrom and supported by rollers in all other positions.

What I claim in t-he foregoing as my i11- vent-ion and desire to Secureby Letters Patent, is y l. Making and arranging a sliding Wicket gate insuch manner, that When shut, it shall rest upon its seat and makev atight joint, but when moving to or from its Closed position,

i shall be raised from its seat, and supported on Wheels to diminish thefriction', and con-v sequently, the expenditure of power required toopen or close it; the power for operating it, being applied through alever (or it-s equivalent) so as to move the gate very slowly but Withgreat force until it is started from its seat and the Weight thrown uponthe friction Wheels, and then, to act upon it With diminished force butmove it faster until it is fully open, thus counterbalanoing, as near asmay be, the force and the resistance.

2. I do not claim the mere counterbalancing of the Weight'of the gateand the pressure of the Water on its upper edge, by means of thepressure -of the Water acting upon a Flange at its lower edge, but WhatI do claim, is, placing a liange for this purpose in an inclinedposition, substantially as described, so that the vena oomfmca shall notprevent t-he issuing Water from pressing against it.r

JOHN JACK.

Witnesses FREDERICK DAVIDSON, ROBERT HAYNES.

